There's no such thing as the contemporary novel. Before I seem the complete reactionary, let me add that I've happily joined in many discussions about "the contemporary novel" where what that usually, unproblematically means is novels that have appeared recently or may appear soon. But the novel that's contemporary in the sense of being wholly "of now" is an impossibility, if only because novels may take years to write, so the "now" with which they begin will be defunct by the time they're finished. Nonetheless, the idea of the novel that's wholly of now persists. There's an undeniable thrill in seeing what's most current in our lives offered back to us in fictional guise, but it soon dates and it's never enough.

When we read novels of the past we're apt to think that they depict a world contemporary to them – that what is Dickensian about Dickens involved his constantly keeping abreast of his times. In fact his novels often look back a decade or more. War and Peace, was written in the 1860s but set during the Napoleonic wars. Since one of his themes was war, Tolstoy might have chosen the Crimean war of the mid-1850s, of which he had direct experience, and he did write about the Crimea in his book Sebastopol, but that's a work of brilliant reportage. He clearly wanted some distance and he knew the difference between a novel and a brilliant report. When Tolstoy died Proust was beginning a novel-sequence which would take the rest of his life and so was never going to be "of now", and its title proclaims one of the things that the novel as a form is inherently about: the passage of time.

The proper medium for what is of now is not the novel but journalism. When we say "the papers" the point gets missed, but the French word "journal" spells it out: what belongs to the day. I lived once in Greece where the word for newspaper is "ephemeritha", an exact equivalent of the French, though to an English ear rather odd. Every time I bought a newspaper there was the subliminal joke that I was buying an "ephemeral". But the joke catches a truth about journalism and about any attempt to capture the "now". Today's news, which may be yesterday's anyway, will be eclipsed tomorrow.

One of the principal things novels can do is depict and explore this very transitoriness. They're there to take the long view, to show change and evolution, human behaviour worked on by time. But none of this means that novels, which can never be strictly of now, cannot have their own kind of "nowness" or have something which actually out-thrills the thrill of the merely contemporary. They can have immediacy.

Why read a novel written 150 years ago and set 50 years before then, why make that double historical leap, if there's not something in Tolstoy's writing that makes us livingly feel that "then" has become "now", that as it is for us so it was for "them" – that provides an instant human connection which actually liberates us from being pathetic creatures of the contemporary? Why undertake the journey of any novel of any period unless to encounter that uncanny, arresting sensation: "I've been here too"?

The word story means something different for journalists from its meaning for novelists. It really means "report", and when journalists favour "story" perhaps they betray a wish to be more than reporters. Conversely, when some big event occurs in the world, something that may even be called world-changing, it's the task of journalists to relay it to us and analyse it, though some novelists may also feel impelled hastily to address such events from a variety of motives, pure and impure. One of them may be envy of the prerogative of journalists and of the genuine powers of reportage, another may be the desire to appear momentously "of now".

After 9/11 (and how that formula demonstrates the working of time), I wondered if I might ever write a novel about it or about the consequent "war on terror", or about Iraq. All these things have now found their way, years after the original event, into my latest novel, and I say "found their way" because the process was unplanned, mysterious and oblique and the novel is about many other things, such as cattle disease, which isn't obviously connected with 9/11 or Iraq, though it was in recent times the stuff of much journalistic coverage.

The novel, Wish You Were Here, tells the story of the return of a dead British soldier from Iraq to England. By inference alone it would be about the world after 9/11, but it's also about a world before 9/11 and a world unchanged by 9/11, which doesn't mean a world untouched by change. It's set in 2006. Does that make it contemporary? I don't know.

The Iraq war was still going on in 2006. It's over now, but it's certainly not over in some of its terrible consequences, and there's a continuing, connected war in Afghanistan. Whenever I hear those grim bulletins that end with the words "next of kin have been informed" I might have the thought that my novel isn't just "contemporary", but is actually, a year after it was completed, about what's happening now. I'm keeping abreast of my times. But that would be a cheap and distasteful thought. I hope my novel has something of the nowness which is the novel's kind of nowness and is compatible with the long view. I hope that it's entirely a novel and not a report.